Disc rotor retraction system
AssigneeThe Boeing Company
InventorDaniel M. Podgurski
Life of this patent
Estimating the term…
Abstract
A disc rotor blade retraction system includes a main blade spar incorporating a hydraulic cylinder and having a screw thread. A ball screw is concentrically carried within the main blade spar and is operably connected to a ball nut which has an outboard end connected to an intermediate spar with a hydraulic piston received for reciprocation in the hydraulic cylinder. A first geared actuator engages the ball screw and a second geared actuator engages the main blade spar screw thread. A hydraulic fluid accumulator providing pressurized hydraulic fluid is connected to an outboard end of the hydraulic cylinder and a controller actuates the first and second geared actuators.
Claims20
A disc rotor blade retraction system comprising:
- a main blade spar incorporating a hydraulic cylinder and having a screw thread;
- a ball screw concentrically carried within the main blade spar and operably carrying a ball nut having an outboard end connected to an intermediate spar and a hydraulic piston received for reciprocation in the hydraulic cylinder;
- a first geared actuator operably engaging the ball screw;
- a second geared actuator operably engaging the main blade spar screw thread;
- a hydraulic fluid accumulator connected to an outboard end of the hydraulic cylinder;
- and,
- a controller for actuation of the first and second geared actuators.
A disc rotor system comprising
- a plurality of rotor blades, each blade having a tip aero panel, a mid aero panel and a root aero panel, each blade having a retraction system supported by a rotor hub and incorporating
- a main blade spar carrying the root aero panel and incorporating a hydraulic cylinder, said main blade spar having a screw thread;
- a ball screw concentrically carried within the main blade spar operably carrying a ball nut having an outboard end connected to an intermediate spar carrying the mid aero panel and further connected to a hydraulic piston received for reciprocation in the hydraulic cylinder, said intermediate spar connected at an outboard end to the tip aero panel;
- a first geared actuator operably engaging the ball screw;
- a second geared actuator operably engaging the main blade spar screw thread;
- a hydraulic fluid accumulator connected to an outboard end of the hydraulic cylinder;
- a controller fir simultaneous actuation of the first and second geared actuators associated with each blade;
- and,
- a disc fairing supported by the rotor hub.
A method for operation of a disc rotor blade comprising:
- commanding retraction of a plurality of blades;
- for each blade,
- setting a solenoid valve for flow through a check valve for hydraulic fluid to flow from an accumulator;
- providing power to a first geared actuator;
- rotating a ball screw responsive to the geared actuator and with the assistance of pressurized hydraulic fluid from the accumulator acting on a piston head, telescopically withdrawing a tip aero panel connected to a ball nut into a mid aero panel;
- withdrawing the nested tip and mid aero panels into a root aero panel;
- upon reaching a retraction limit of the ball nut on the ball screw, removing power from the geared actuator;
- providing power to a second geared actuator for each blade;
- and,
- rotating a nut with the second geared actuator, said nut acting on a thread on a main blade spar carrying the root aero panel to withdraw the main blade spar into a disc fairing.
Dependencies are inferred from the claim text.